The Study On Delta Front Reservoir Architecture Of Sha3 Up-sub-member,Wen38 Block

Sha 3 up-sub-member of Wen 38 Block,Wendong Oilfield deposits delta front sedimentary environment.Delta front is the most important reservoir of delta sedimentary environment as well as an important field of oil and gas exploration.Most of the oilfields of our country have been in their middle and later period right now.Been controlled of the anisotropy of reservoir,remaining oil appears uneven distribution.Therefore,it is essential to enforce the study of architecture of delta front reservoir.With which we could make clear how the sedimentary micro-facies distribution and evolution as well as the characteristics of reservoir architecture,so as to reveal remaining oil distribution schema.In this thesis,we take a case of Sha3 up-sub-member in Wen38 block,being guided by the principle of sequence stratigraphy,sedimentology,etc.to study the delta front reservoir architecture of study area using the materials of seismic,cores and logging.With the achievement of stratigraphic systems,we make clear the staging hierarchy of delta front reservoir architecture in Sha3 up-sub-member,Wen38 Block.Then,we study the reservoir architecture scale as well as the distribution characteristics.According to the study,Sha3 up-sub-member in Wen38 Block is mainly controlled by north-western provenance.The delta front sedimentary environment of this area could be further divided into 5 micro-facies: under-water channel,under-water channel flank,sheet sand,estuary bar,tributary bay.Among which,the under-water channel is the most important sand body.The form of under-water channel could be divided as single stripe,fork and contiguous form.Sheet sand could be divided into river-dominated style and wave dominated style.The width of single-channel is between 80 m to 150 m.Single-channels inner mix-channels,which could be 2200-mile-wide and 5-mile-wide,usually appear side direction joined or side direction overlay.